GUI crashes on startup after creating a wallet previously

[rkrux]

Is there an existing issue for this?

• I have searched the existing issues

Current behaviour

Note: The issue is present in testnet too, not only regtest.

The GUI crashes in regtest immediately on start. It did work once initially but has been crashing since, tried quite a few times.

Expected behaviour

The GUI should not crash in regtest, just like it doesn't in main or test environments.

Steps to reproduce

Regtest conf file to use:

➜  Bitcoin cat $BITCOIN_DATA_DIR/bitcoin-reg.conf
regtest=1
[regtest]
port=28333
rpcport=28332
rpcuser=test
rpcpassword=test
bind=127.0.0.1:28334
bind=127.0.0.1:28335=onion

New data directory setup:

➜  ~ mkdir /tmp/gui-node-1
➜  ~ cp $BITCOIN_DATA_DIR/bitcoin-reg.conf /tmp/gui-node-1
➜  ~ cd /tmp/gui-node-1
➜  gui-node-1 l
total 8
drwxr-xr-x   3 rkrux  wheel    96B Dec 19 15:48 .
drwxrwxrwt  10 root    wheel   320B Dec 19 15:46 ..
-rw-r--r--   1 rkrux  wheel   123B Dec 19 15:48 bitcoin-reg.conf

Run GUI (bitcoin-qt): Works first time, no wallet right now.

➜  ~ $BITCOIN_BUILD_BIN_DIR/bitcoin-qt -datadir=/tmp/gui-node-1 -conf=/tmp/gui-node-1/bitcoin-reg.conf

Create a wallet within the GUI (wallet name eg: gui-node-wallet) and close the GUI.

Run GUI (bitcoin-qt) again - fails now with the below error:

➜  ~ $BITCOIN_BUILD_BIN_DIR/bitcoin-qt -datadir=/tmp/gui-node-1 -conf=/tmp/gui-node-1/bitcoin-reg.conf
Error: SQLiteDatabase: Failed to configure serialized threading mode: bad parameter or other API misuse

Data directory state now:

➜  gui-node-1 l /tmp/gui-node-1
total 8
drwxr-xr-x   4 rkrux  wheel   128B Dec 19 16:08 .
drwxrwxrwt  10 root    wheel   320B Dec 19 16:07 ..
-rw-r--r--   1 rkrux  wheel   123B Dec 19 16:07 bitcoin-reg.conf
drwx------  13 rkrux  wheel   416B Dec 19 16:11 regtest
➜  gui-node-1 l /tmp/gui-node-1/regtest/
total 600
drwx------  13 rkrux  wheel   416B Dec 19 16:11 .
drwxr-xr-x   4 rkrux  wheel   128B Dec 19 16:08 ..
-rw-------   1 rkrux  wheel     0B Dec 19 16:08 .lock
-rw-------   1 rkrux  wheel    37B Dec 19 16:11 anchors.dat
-rw-------   1 rkrux  wheel   221B Dec 19 16:08 banlist.json
drwx------   7 rkrux  wheel   224B Dec 19 16:08 blocks
drwx------   7 rkrux  wheel   224B Dec 19 16:10 chainstate
-rw-------   1 rkrux  wheel    18K Dec 19 16:11 debug.log
-rw-------   1 rkrux  wheel   242K Dec 19 16:11 fee_estimates.dat
-rw-------   1 rkrux  wheel    27B Dec 19 16:11 mempool.dat
-rw-------   1 rkrux  wheel   4.1K Dec 19 16:11 peers.dat
-rw-------   1 rkrux  wheel   242B Dec 19 16:11 settings.json
drwx------   3 rkrux  wheel    96B Dec 19 16:11 wallets
➜  gui-node-1 l /tmp/gui-node-1/regtest/wallets
total 0
drwx------   3 rkrux  wheel    96B Dec 19 16:11 .
drwx------  13 rkrux  wheel   416B Dec 19 16:11 ..
drwx------   3 rkrux  wheel    96B Dec 19 16:11 gui-node-wallet
➜  gui-node-1 l /tmp/gui-node-1/regtest/wallets/gui-node-wallet
total 48
drwx------  3 rkrux  wheel    96B Dec 19 16:11 .
drwx------  3 rkrux  wheel    96B Dec 19 16:11 ..
-rw-------  1 rkrux  wheel    24K Dec 19 16:11 wallet.dat

Relevant log output

2025-12-19T10:48:12Z Using data directory /tmp/gui-node-1/regtest
2025-12-19T10:48:12Z Config file: /tmp/gui-node-1/bitcoin-reg.conf
2025-12-19T10:48:12Z Config file arg: regtest="1"
2025-12-19T10:48:12Z Config file arg: [regtest] bind="127.0.0.1:28334"
2025-12-19T10:48:12Z Config file arg: [regtest] bind="127.0.0.1:28335=onion"
2025-12-19T10:48:12Z Config file arg: [regtest] port="28333"
2025-12-19T10:48:12Z Config file arg: [regtest] rpcpassword=****
2025-12-19T10:48:12Z Config file arg: [regtest] rpcport="28332"
2025-12-19T10:48:12Z Config file arg: [regtest] rpcuser=****
2025-12-19T10:48:12Z Setting file arg: wallet = ["gui-node-wallet"]
2025-12-19T10:48:12Z Command-line arg: conf="/tmp/gui-node-1/bitcoin-reg.conf"
2025-12-19T10:48:12Z Command-line arg: datadir="/tmp/gui-node-1"
2025-12-19T10:48:12Z Using at most 125 automatic connections (1024 file descriptors available)
2025-12-19T10:48:12Z scheduler thread start
2025-12-19T10:48:12Z Using wallet directory /tmp/gui-node-1/regtest/wallets
2025-12-19T10:48:12Z Using SQLite Version 3.43.2
2025-12-19T10:48:12Z init message: Verifying wallet(s)…
2025-12-19T10:48:12Z [warning] SQLite Error. Code: 21. Message: misuse at line 185687 of [1b37c146ee]
2025-12-19T10:48:12Z [error] SQLiteDatabase: Failed to configure serialized threading mode: bad parameter or other API misuse

2025-12-19T10:48:14Z Shutdown in progress...
2025-12-19T10:48:14Z scheduler thread exit
2025-12-19T10:48:14Z Shutdown done

How did you obtain Bitcoin Core

Compiled from source

What version of Bitcoin Core are you using?

master@13891a8a685d255cb13dd5018e3d5ccc18b07c34

Operating system and version

MacOS Sequoia (15.4)

Machine specifications

No response

[furszy]

Can you check the directory permissions please

[maflcko]

Is this really gui-specific? Does it not happen with bitcoind?

[rkrux]

Is this really gui-specific? Does it not happen with bitcoind?

Yes, it seems to be GUI specific, and doesn't happen with bitcoind alone.

Can you check the directory permissions please

I did and noticed that the regtest and testnet subdirectories didn't have the r|x permissions for group and others, unlike the data directory. I gave those permissions to them but I don't believe it was the issue - when I was looking into the directory permissions, I also noticed that one regtest subdirectory was present within the regtest subdirectory. I rm-rf'ed it and ran the GUI again, it worked then.

However, the GUI seems to be creating this additional subdirectory every time it is run, and I have to delete it every time, otherwise the same error pops up. If I run the GUI without the -walletdir argument so that the additional subdirectory is not created, the GUI runs but it is not able to find the already present wallets that I have in regtest, so this argument seems necessary to me, but at the cost of deleting the additional subdirectory after the next run.

[maflcko]

I don't think datadir is supposed to include the regtest portion?

Otherwise, the dir structure will end with regtest/regtest, no?

[maflcko]

At least that is what I get when running:

$ ./bld-cmake/bin/bitcoin-qt -regtest -datadir=/tmp/regtest/ -printtoconsole | grep 'Using data'
2025-12-18T11:03:50Z Using data directory /tmp/regtest/regtest

You are setting regtest in the conf file, so that is different, and it may be good to check what the expected interaction is there:

2025-12-17T10:22:16Z Default data directory /Users/rkrux/Library/Application Support/Bitcoin
2025-12-17T10:22:16Z Using data directory /Users/rkrux/Library/Application Support/Bitcoin/regtest
2025-12-17T10:22:16Z Config file: /Users/rkrux/Library/ApplicationSupport/Bitcoin/bitcoin-reg.conf
2025-12-17T10:22:16Z Config file arg: regtest="1"

[rkrux]

I don't think datadir is supposed to include the regtest portion?

If I run without the regtest portion, I get the same error. If I run without it and without the -walletdir as well, then too the same error.
I suspect that the GUI always tries to create the regtest subdirectory and errors out if it's already present - at least with my combination of the arguments and configuration file.

[rkrux]

From the debug log:

2025-12-18T11:05:02Z Default data directory /Users/rkrux/Library/Application Support/Bitcoin
2025-12-18T11:05:02Z Using data directory /Users/rkrux/Library/ApplicationSupport/Bitcoin/regtest/regtest
2025-12-18T11:05:02Z Config file: /Users/rkrux/Library/ApplicationSupport/Bitcoin/bitcoin-reg.conf
2025-12-18T11:05:02Z Config file arg: regtest="1"
2025-12-18T11:05:02Z Config file arg: [regtest] bind="127.0.0.1:28334"
2025-12-18T11:05:02Z Config file arg: [regtest] bind="127.0.0.1:28335=onion"
2025-12-18T11:05:02Z Config file arg: [regtest] port="28333"
2025-12-18T11:05:02Z Config file arg: [regtest] rpcpassword=****
2025-12-18T11:05:02Z Config file arg: [regtest] rpcport="28332"
2025-12-18T11:05:02Z Config file arg: [regtest] rpcuser=****
2025-12-18T11:05:02Z Command-line arg: conf="/Users/rkrux/Library/ApplicationSupport/Bitcoin/bitcoin-reg.conf"
2025-12-18T11:05:02Z Command-line arg: datadir="/Users/rkrux/Library/ApplicationSupport/Bitcoin/regtest"
2025-12-18T11:05:02Z Command-line arg: walletdir="/Users/rkrux/Library/ApplicationSupport/Bitcoin/regtest/wallets"
2025-12-18T11:05:02Z Using at most 125 automatic connections (1024 file descriptors available)
2025-12-18T11:05:02Z scheduler thread start
2025-12-18T11:05:02Z Using wallet directory /Users/rkrux/Library/Application Support/Bitcoin/regtest/wallets
2025-12-18T11:05:02Z Using SQLite Version 3.43.2
2025-12-18T11:05:02Z init message: Verifying wallet(s)…
2025-12-18T11:05:02Z Using /16 prefix for IP bucketing
2025-12-18T11:05:02Z init message: Loading P2P addresses…

[maflcko]

Actually, parsing the conf file should clear the old/stale datadir value:

src/common/config.cpp-    // If datadir is changed in .conf file:
src/common/config.cpp:    ClearPathCache();
src/common/config.cpp-    if (!CheckDataDirOption(*this)) {
src/common/config.cpp-        error = strprintf("specified data directory \"%s\" does not exist.", GetArg("-datadir", ""));
src/common/config.cpp-        return false;
src/common/config.cpp-    }

Can you reproduce this on Linux?

[rkrux]

Can you reproduce this on Linux?

Sorry, I don't have access to a Linux machine.

You are setting regtest in the conf file, so that is different, and it may be good to check what the expected interaction is there:

I will spend some time checking the expected interaction.

[maflcko]

Can you reproduce this on Linux?

Sorry, I don't have access to a Linux machine.

Fair. It may be possible to install a Linux VM, but this may be tedious.

Another thing could be to create exact steps to reproduce, starting from a fresh folder:

mkdir new_datadir
echo 'regtest=1' > conf
...

This way, other devs on macOS can try to reproduce it.

[rkrux]

Another thing could be to create exact steps to reproduce, starting from a fresh folder:

Good idea - done, helped me in understanding the issue from scratch. Also, updating the issue description with these steps.

Regtest conf file to use:

➜  Bitcoin cat $BITCOIN_DATA_DIR/bitcoin-reg.conf
regtest=1
[regtest]
port=28333
rpcport=28332
rpcuser=test
rpcpassword=test
bind=127.0.0.1:28334
bind=127.0.0.1:28335=onion

New data directory setup:

➜  ~ mkdir /tmp/gui-node-1
➜  ~ cp $BITCOIN_DATA_DIR/bitcoin-reg.conf /tmp/gui-node-1
➜  ~ cd /tmp/gui-node-1
➜  gui-node-1 l
total 8
drwxr-xr-x   3 rkrux  wheel    96B Dec 19 15:48 .
drwxrwxrwt  10 root    wheel   320B Dec 19 15:46 ..
-rw-r--r--   1 rkrux  wheel   123B Dec 19 15:48 bitcoin-reg.conf

Run GUI (bitcoin-qt): Works first time, no wallet right now.

➜  ~ $BITCOIN_BUILD_BIN_DIR/bitcoin-qt -datadir=/tmp/gui-node-1 -conf=/tmp/gui-node-1/bitcoin-reg.conf

Create a wallet within the GUI (wallet name eg: gui-node-wallet) and close the GUI.

Run GUI (bitcoin-qt) again - fails now with the below error:

➜  ~ $BITCOIN_BUILD_BIN_DIR/bitcoin-qt -datadir=/tmp/gui-node-1 -conf=/tmp/gui-node-1/bitcoin-reg.conf
Error: SQLiteDatabase: Failed to configure serialized threading mode: bad parameter or other API misuse

Data directory state now:

➜  gui-node-1 l /tmp/gui-node-1
total 8
drwxr-xr-x   4 rkrux  wheel   128B Dec 19 16:08 .
drwxrwxrwt  10 root    wheel   320B Dec 19 16:07 ..
-rw-r--r--   1 rkrux  wheel   123B Dec 19 16:07 bitcoin-reg.conf
drwx------  13 rkrux  wheel   416B Dec 19 16:11 regtest
➜  gui-node-1 l /tmp/gui-node-1/regtest/
total 600
drwx------  13 rkrux  wheel   416B Dec 19 16:11 .
drwxr-xr-x   4 rkrux  wheel   128B Dec 19 16:08 ..
-rw-------   1 rkrux  wheel     0B Dec 19 16:08 .lock
-rw-------   1 rkrux  wheel    37B Dec 19 16:11 anchors.dat
-rw-------   1 rkrux  wheel   221B Dec 19 16:08 banlist.json
drwx------   7 rkrux  wheel   224B Dec 19 16:08 blocks
drwx------   7 rkrux  wheel   224B Dec 19 16:10 chainstate
-rw-------   1 rkrux  wheel    18K Dec 19 16:11 debug.log
-rw-------   1 rkrux  wheel   242K Dec 19 16:11 fee_estimates.dat
-rw-------   1 rkrux  wheel    27B Dec 19 16:11 mempool.dat
-rw-------   1 rkrux  wheel   4.1K Dec 19 16:11 peers.dat
-rw-------   1 rkrux  wheel   242B Dec 19 16:11 settings.json
drwx------   3 rkrux  wheel    96B Dec 19 16:11 wallets
➜  gui-node-1 l /tmp/gui-node-1/regtest/wallets
total 0
drwx------   3 rkrux  wheel    96B Dec 19 16:11 .
drwx------  13 rkrux  wheel   416B Dec 19 16:11 ..
drwx------   3 rkrux  wheel    96B Dec 19 16:11 gui-node-wallet
➜  gui-node-1 l /tmp/gui-node-1/regtest/wallets/gui-node-wallet
total 48
drwx------  3 rkrux  wheel    96B Dec 19 16:11 .
drwx------  3 rkrux  wheel    96B Dec 19 16:11 ..
-rw-------  1 rkrux  wheel    24K Dec 19 16:11 wallet.dat

[rkrux]

In the above experiment, I didn't try changing the data dir or adding the walletdir arg so that the issue is apparent with only one set of arguments and dirs. That's why I believe there is no additional regtest subdirectory created.

[furszy]

@rkrux, I haven't been able to reproduce it, but have an idea of what might be happening. Please try this branch: https://github.com/furszy/bitcoin-core/tree/2025_wallet_db_config_engine and let me know if the issue still occurs. Will rework the fix properly and detail the scenario.